Highly ordered porous anodic aluminum oxide (PAA) membranes were prepared by electrochemical method. By alternating current electrodepositing, Cu-Co alloy nanowire arrays were fabricated in the micro column-shaped holes of porous alumina template in a mixed electrolyte of CuSO4 and CoSO4. The morphology and microstructures of PAA and nanowire arrays were characterized by XRD and SEM. The results show that the surface of Cu-Co nanowire arrays is uniform and regular with a preferred crystal face (111) during growing. And the transmission and polarization spectrum indicate that the sample has good transmittance and extinction ratio. Cu-Co alloy can change some characteristics of the simple metal, and for example, CuCo/PAA has better extinction ratio (30 dB) in near infrared waveband than Cu/Al2O3 (17 dB).